Generally, a tablet printing device prints identification information such as letters or characters (e.g., alphabet, kana, and numeric) or marks (e.g., symbols and figures) on the surface of a tablet in order to identify the tablet. As the tablet printing device, an inkjet tablet printing device, which performs printing on a tablet in a noncontact manner, has been developed due to the ease of changing letters, characters or marks, high print quality, and the like. The inkjet tablet printing device ejects ink (e.g., edible ink) toward a tablet being conveyed by a conveyor belt or the like to print identification information on the surface of the tablet.
There are various types of tablets as a tablet to be printed. The various types of tablets include those having front and back sides. Examples of the tablets having the front and back sides include a tablet with a split line for dividing the tablet on one side. In this tablet, generally, a surface with a split line is regarded as the front side, and a surface without a split line is regarded as the back side. Identification information may be printed on the surface with a split line. Therefore, it is desirable to supply tablets on the conveyor belt with the front side (the surface with a split line) thereof facing up.